Disazo dye and method for its preparation



Patented Feb. 19. 1935 UNITED-STATES.

PATENT OFFICE I 1,991,505 1 1 DISAZO DYE 'AND METHOD on ITS 7 PREPARATION j Henry Jordan, Wilmington, Del.',.assignor to E. I.

du Pont de Nemours & Company, Wilmington, DeL, a corporation of Delaware No Drawing.i""Application May 4, 1932, Serial No. 609,270

18 Claims. (01.26043 This invention relates to azo dyes and more particularly refers to green disazo dyes and methods for their production.

The object of this invention is to produce, gree 5 azo dyes capable of dyeing cotton and regenerated cellulose infast brilliant shades. Another object' is to produce azodyes which may be diaz otized onth'dfiberf and; developed with any of the'us'ual developing solutions to produce fast brilliant shades. A still further object is to produce azo dyes which may be discharged to a'pure white with any of'the ordinary discharge medi-' present invention will probably havethe following general formula: j-o-R; on im-oo-gm,

wherein'Ri represents an aromatic radical not containing a free sulfo orv carboxyl group, R2 40 representsan alkyl group and Ra an aryl group containing a free external amino group.

This invention may be more completely understood by reference to the following examples:

. 'Erample l e Ninety-three (93 parts or aniline were diazotized in the usual way. 'I'he'diazosolutio'n wasadded to asolution of 253 parts of l-amino-2- naphthol-methyl ether-fi-su1fonic acid in 5000 parts of water and 2 80 parts of sodium acetate crystals. The couplingtemperature was 5l0 C. 60 The reaction should be acid to litmus. After stirring over night the coupling was finished. It was heated to 70 C. and filtered; The filter cake was then dissolved in 6000 parts of water and 60 parts ofsodium hydroxide. 90 parts of sodium nitrite was added and the'mixture was then added 'to'a mixture of ice and 00 parts of a 31 hydrochloricacid solution,'maintaining the tempera-' ture of 'the diazotiz ation at 0-5 C. After stirringfor about 1 hour the diazoti'zation should be Three hundred'fifty-eight (358) parts of pamino benzoyl- 1 amino -8 naphthol 4 sulfonic acid were dissolved in 3000jparts of water and 53 pa'rtsbf sodium carbonate "2000 parts of ice were added to the solution and-after that 1000 parts ofjs'fodium chloride; thus reducing the temperature to about 10 C." There was then added 320 partsof a 28% ammonium hydroxide solu-' tion and the diazo solution was then added slowly to thismix'ture, maintaining a" temperature of 10to -5 C. More ice may be added if necesadded the coupling was allowed to stir for half an hour. The green dye was precipitated out of solution and filtered cold.f For purification the filter'cake-wasstirred up again with 5000 parts of waterfheated to 70 C.,"75"parts of sodium carbonate and 500 parts'of salt were added'and then the dye was filtered'again. In its dry ground form it represented a dark bronzy powder, soluble in cold water with-a bluish-violet color which turned to a'bright bluish-green when heated to about TO-80 C. In concentrated sulfuric acid it was solublewith a. dull grey coloration. It dyed cotton and'rayoninbright bluish-green shades which, when diazotized on the fiber and developed with phenyl-methyl-pyrazolone; changed to a bright very yellowish-green. The developed dye-.- ings showed a remarkable fastness. to washing; they discharged with a reducing discharge medium, as sodium hydrosulfite, to a pure white When'developed with aceto-acetanilide instead of pyrazolone the shades obtained were considerably bluer V and slightly brighter than those with pyrazolone. V i

Thenew dye most probably had the following formula:

O aNB since on reduction with stannous chloride'there was obtained: aniline, 1:4-diamino-2-methoxy- 'n'aphthalen-G-sulfonic acid and p-amino-benzoyl 1 amino 8-hydroxy 'l-amino-naphthalenefl-sulfonic acid.

'sary. After all'the diazo "compound had been I '7 N? This dye represented in itslldry, ground form a dark bronzy powder, soluble in cold water with a blue coloration, which turned to .a, bright green on heating to -80? C. In concentrated sulfuric acid the dyedissolvedwith a dark blue coloration. On reduction with stannous chloride the same products were obtained as in Example 1 except parag-phenetidine was obtained-.insteadgof aniline. M 1

In the above examples, inplace-of aniline and para-phenetidine, other amino-compounds of the aromatic series whichdo not contain a free sulfo or carboxyl group may be used. Some of the compounds which were used with very satisfactory results were pchloroaniline, o-chloroaniline, :m-chloroaniline, .ortho-, meta-, and para toluidine, the various' xylidines,anisidines, cresi dines, amino-benzamides, monoand 'di-alkylbenzamides, as well as members ofthe aminonaphthalene class.- I p The 1 amino-Z-naphthol methyl-ether-G-sul fonic acid may be replaced by the corresponding 7-sulfonic acid; and also by other alkyl-ether derivatives, such as ethyl or butyl, without im- 7 pairing the beautiful brilliant shades of the fin:

ished dye. f

The third intermediate, para-.amino-benzoyl-lamino-8-naphthol 4-sulfonic acid, may likewise be replaced by various other compounds such'as the 'meta-amino-benzoyl compounds. Thessulfonic ,acid group may occupy some jposition other than the four position, such-as l-ainino-8-naphthol-B-sulfonic acid. The amino-benzoyl radical may also have substituted therein'various groups such as the alkylyalkoxy, hydroxy,-halogen, :and nitro groups. l

The compounds produced by the process of the present invention have an exceptional affinity for cotton and regenerated cellulose; On this material they produce valuable bright green' shades'. These shades arevery fast to washing 'and may be discharged to a pure white with an ordinary discharge medium. Since the end component contains afree amino group the disaz-o dye may be d-ia zotized on the fiberand developed thereon with any of the customary deye1oping'solutions.

OaNa

manufacturer can ;;choose the compounds' 'which are cheaperand more accessible; 4 As many apparently widely different embodito be understood that I do not limit myself to the specific embodiments thereof except as definedin the appended claims. V

I claim: V

1. The process of producing a disazo dyewhich comprises diaz'otizing an aminoazo compo upd prepared by coupling an aromatic diazo com pound to .1eamino-2-naphthol-alkyl-ether-sul-:-

'fonic acid, and coupling the resulting diazo azo free sulfo or carboxyl group, .to 1-amino-.2-naph thol-alkyl ether-G -sulfonic acid, and -coup1ing, the resulting diazo-azo compound to an amino,- benzoyl-hamino-B-naphthol-sulfonic acid.

4, The process of producing Ea -disazo' dye which comprises diazotizing an aminoazo com pound prepared by coupling diazotized p-phenetidine' to 1 amino- 2 naphthol-methyl-ether- G-sulfonic acid and coupling the; resulting diazo-azo compound to 'pino-benzoyl-lamino-8-naphthol-4 sulfonic acid 5. A disazo dye having the-general formula:

/SO3H\- S OaH V wherein R1 is an aromatic radical of the benzene or naphthaleneseries, notcontaining a free sulfo or carboxyl group,R2 .i's.an.alkyl group, and R is a .phenyl group containing 'a free external amino group;

'm'ents of this invention may be made without-- departing from the. spirit and scope thereof it is 7. A disazo dye having the formula:

R1 OH 1111100123 wherein R1 is an aromatic radical of the benzene or naphthalene series, not containing a free sulfo or carboxyl group, R2 is an alkyl group, and

R3 is a phenyl group containing a free external amino group.

3. A disazo dye having the general formula:

SO3H\-\ wherein R is an alkyl group, and X is a hydrogen, alkyl, alkoxy or halogen group.

9. A disazo dye having the following formula:

. 0R2 OH NIH-CO R SOaH SO'H wherein R1 and R2 represent alkyl groups.

10;The azo dyestuffs of the general formula:

wherein the benzoyl radical may be substituted by alkyl, alkoxy or halogen.

11. A disazo dye having the formula:

0.. NHCO N od;

OH NH-CO 15. The disazo dye substantially identical with that produced by the process ofclaim 1, which produces bright bluish-green shades on vegetable fibers, and which when diazotized on the fiber and developed with phenyl-methyl-pyrazolone produces bright yellowish-green shades exceptionally fast to washing. I

- 16. The disazo dye substantially identical with that produced by the process of claim2, which produces bright bluish-green shades on vegetable fibers, and which when diazotized on the fiber and developed with phenyl-methyl-pyrazolone produces bright yellowish-green shades exceptionally fast to washing. I

17. The disazo dye substantially identical with that produced by the process of claim 3, which produces bright bluish-green shades on vegetable fibers, and which when diazotized on the fiber and developed with phenyl-methyl-pyrazolone produces bright yellowish-green shades exceptionally fast to washing.

18; The disazo dye substantially identical with 12. A disazo dye having the following formula:

OH Nn-o 0 that produced by the process of claim 4, which produces bright bluish-green shades on vegetable fibers, and which when diazotized on the fiber and developed with phenyl-methyl-pyrazolone produces bright yellowish-green shades exceptionally fast to washing.

' HENRY JORDAN. 

